Machine component time recorder



Feb. 20, 1968 G. T. MAYS MACHINE COMPONENT TIME RECORDER Filed Aug. 18, 1965 UnitedStates Patent Ofilice 3,369,359 Patented Feb. 20, 1968 3,369,359 MACHINE COMPONENT TIME RECORDER George T. Mays, 135 W. Henfer Park, New Orleans, La. 70123 Filed Aug. 18, 1965, Ser. No. 480,716 7 Claims. (Cl. 58-145) ABSTRACT OF THE DISCLOSURE A method and apparatus for carrying out a preventative maintenance program on a machine. Electrical circuit means are provided to automatically determine the individual total operating time of various critical components in the machine. These components are removed at the end of predetermined time intervals and replaced with new components according to a schedule based on the average useful safe life for the respective critical components. The invention is particularly adapted for use in a preventative maintenance program on a dual cylinder reciprocating mud pump.

This invention relates to a device for recording the operating time of components in a machine. The invention also relates to a method of maintaining a machine having a plurality of components subject to wear.

In most all machines having a number of moving parts certain parts are likely to wear more than others and require periodic replacement. This is particularly true in certain very heavy and costly machines, in particular mud pumps used for circulating drilling mud in an earth bore drilled for an oil or gas well. Mud pumps used in drilling present day deep wells cost in excess of $50,000 each. Due to the extremely abrasive nature of most drilling muds certain components in mud pumps have relatively short lives and the pump must be shut down frequently for replacement of the parts.

Most mud pumps used today utilize a pair of double acting reciprocating pistons, each operating in separate cylinders arranged in side-by-side alignment and driven in opposite directions by a rotating crankshaft powered by diesel or diesel-electric motors. Each half of the pump assembly contains a cylinder having a replaceable liner therein. Each liner has a piston therein carried by the end of a piston rod. A rod packing assembly seals the piston rod where it projects through one end of the cylinder. Since each cylinder is double acting, a suction valve and a discharge valve assembly is provided at each end of each cylinder.

The abrasive nature of most mud fluids and the high pressures often necessary, e.g. 3,000 psi. on many wells having depths in excess of 10,000 feet, cause a number of pump parts to have relatively short life. For example, the life of the rod packing material ranges from about 100 to about 600 operating hours, piston rods have a life ranging from about 300 to about 600 operating hours, with pistons having about the same life as do piston rods. Piston liners normally have a life span of from about 600 hours to about 1200 hours, while suction and discharge valves and valve seats have a life of from about 1000 to about 2000 hours. The actual life of each of the foregoing components is determined by a number of factors. Among the more important factors in pump component life span are (l) the physical nature of the drilling fluidi.e. density, abrasiveness, viscosity; (2) the pressure at which the pump is required to operate; (3) the speed at which the pump is operated; and (4) the condition and age of the pump.

For many years mud pumps were placed in service and used until a mechanical failure occurred which required the pump to be shut down and repaired. Usually only the part that failed was replaced, and often only a short time later another worn part would fail requiring the pump to be shut down for repair again. Recently there have been efforts by some well drilling companies to institute preventative maintenance programs on their mud pumps. In these programs the objective is to change out worn pump components after they had been run for a predetermined length of time, i.e. their normal life span. It has been determined that it is far cheaper and causes less drilling rig shut down to change the short life components of a mud pump on a fixed life schedule rather than to run the components to failure and then repair the pump. I

The key to a successful preventative maintenance program is the accurate recording and accumulation of the total operating time of each one of the critical replaceable components, e.g. rods, rod packing, liners and pistons on a mud pump. Failure or errors in the accumulation of the total operating time causes the parts to be run to the point of failure or either replaced before their normal span has been reached. Heretofore, the total operating times of the various components of a mud pump have been determined by manually recording each operating period on log sheets and totaling to accumulate the total time on each component. This procedure has proved very unsatisfactory because of the complexity of the time logging job and the large number of chances for human error. On each eight hour tour or shift a different equipment operator is responsible for entering the added hours each component in each cylinder has been operated. The normal log sheet could only accommodate operating times for one week and requiredposting of eighteen separate (nine for each side of the pump) time totals for the pump components on to a new log sheet or to an accumulating total sheet. This alone causes a large number of errors in transferring the running hour totals. However, a major source of error occurring in the man ual logging of total operating times for mud pump components is caused by confusion as to which is the left and which is the right side of the mud pump. Since the left and right hand sides have identical components the actual total operating times would be reversed if a different operator regarded the left side as the right side of the pump. This causes all of the parts to be changed either early or late in the planned program. Thus there has been a need for a device which would automatically accumulate the total operating time for each replaceable component in the left and the right hand sides of a mud pump so that a successful preventative maintenance program could be carried out.

It is an object of this invention to provide a device for automatically recording the total operating time of individual components in a machine.

Another object of this invention is to provide a device for automatically recording the operating time of individual components in a machine which has a number of duplicate components.

It is still another object of this invention to provide a device for automatically recording the operating time of individual components in a machine, which device is of simple construction and functions reliably.

The foregoing and other objects of this invention are realized in a device for recording the operating time of machine components which includes an electrical circuit means. Switch means in the circuit means is adapted to complete the circuit means when the machine is operating and open the circuit means when the machine is not operating. A first electrically operated time recording element is connected to the circuit means. A second and a third electrically operated time recording element is connected to one leg 'of the circuit means. Switch means is provided for connecting either the second or the third time recording element to the other leg of the circuit means.

In another embodiment of the present invention there is provided a device for indicating the running time of individual components of a machine having a plurality of dual components comprising a first pair of electrical time recording means for individually recording the operating time of each component in a first set of components in the machine. Circuit means is provided which is connected to the first pair of electrical time recording means. A switch is provided in the circuit which switch is closed when the machine is in operation and open when the machine is not in operation. A second pair of electrical time recording means is connected to one leg of the circuit means.

Means is provided to connect the other leg of the circuit to one of the second pair of electrical time recording means to record the total operating time of one single component of the machine. Means is provided to disconnect the other leg of the circuit from the one of the second pair of electrical time recording means and to connect the other of the second pair of electrical time recording means to the other leg of the circuit to record the total operating time of the replacement component for the one single component. A third pair of electrical time recording means is connected to one leg of the circuit means. Means to connect the other leg of the circuit to one of the third pair of electrical time recording means to record the total operating time of another single component of the machine is provided. Means is provided to disconnect the other leg of the circuit from the one of the third pair of electrical time recording means and to connect the other of the third pair of electrical time recording means to the other leg of the circuit to record the total operating time of the replacement component for the another single component.

The method aspect of the present invention for maintaining a machine having a plurality of different type replaceable components, each type having a different average useful life span, may be carried out by installing a new component for each of the different types of replaceable components. The total running time of each of the new components is then automatically accumulated and displayed. When the total running time of each of the new components equals to the average useful life for that type component the new components are removed. Each type of expended replaceable component removed i replaced with a another new component. Thereafter the accumulation of running time, removal of worn parts and replacement is continued as described above.

The drawing depicts an electrical schematic wiring diagram for a device constructed in accordance with the present invention for recording the operating time of components in a machine. The device is shown connected to an exemplary double acting reciprocating mud pump, portions of which are broken away to more clearly depict the components of the pump.

The mud pump, designated generally by the numeral 20, has a power assembly housing 21 which contains the crankshaft, connecting rods and other power components (not shown). A reciprocating pump assembly designated generally 22, is connected to the front end of the housing 21.- The pump assembly includes a left cylinder 23 and a right cylinder 24. The left cylinder contains a left cylinder liner 25 which is removable through the front end of the cylinder. The right cylinder contains a like right cylnder liner 26. A left piston 27 is slidably received in a left liner 25 and is attached to one end of a left piston rod 28. The left piston rod is sealed by a left rod packing 29. A right liner 26 contains the right piston 30 carried by one end of the right piston rod 31. The right piston rod is sealed by a right rod packing 32. A main suction line 33 feeds mud to a left suction manivalves 36-36, one on each end of the manifold, seat in the left valve seats 3'737 and control the inflow of mud to the left cylinder 23. A like pair of right suction valves (not shown) seat in the right valve seats (not shown) in the right suction manifold 35. The right cylinder 24 is provided with a discharge manifold 40. Right discharge valves 41-41 are located at each end of the right manifold and seat on the right seats 4242. Like left discharge valves 4343 and left valve seats 44-44 are provided in the left discharge manifold (not shown). A mud discharge line 45 carries the mud to the swivel head on the top of drill string.

The time recording device includes a lower leg wire 46 and an upper leg wire 47 for supplying the electrical current to the operating elements of the time recording device. One end of the lower leg wire 46 is connected to a male plug 48 for connection to a 110 v. AC source. The upper leg wire 47 is connected to the plug 48 and then to an on-off switch 49. A lead wire 51 connects switch 49 to one side of a normally open pressure actuated switch 50 which may be installed in the mud discharge line 45. Another lead wire 52 connects the other side of switch 50 to the upper leg wire 47. If desired, pressure switch 50 may be installed in the air supply line leading to the air clutch connecting the diesel motor to the mud pump so that when air pressure is applied to engage the clutch and drive the pump, the switch 50 will be closed. When switch 49 is closed pilot light P-5 goes on to indicate that the device has electrical power. When the mud pump begins operation, mud pressure in discharge line 45 (or the air pressure to the clutch) actuates pressure switch 50 and supplies current to the upper leg wire 47. Electrical timer T-l is connected directly to the upper leg 47 and the lower leg 46 and operates each time the pump operates. This timer is used for accumulating the operating time of the left liner 25. Timer T-2 has one lead connected to lower leg 46 and the other lead is connected through switch 53 to upper leg 47. This timer is used to accumulate the operating time of the left piston No. 1. Timer T-3 is connected in the same manner as timer T -2 and is used to accumulate the operating time of left piston No. 2. Normally a single liner has a life span equal to that of two pistons, so it is necessary to keep a record of the life of two pistons before zeroing the left liner timer T-l when a new liner is placed in the left cylinder. Pilot lights P-1 and P-Z indicate visually which timer, T-Z or T-3, respectively, is connected to the circuit through switch 53. Timer T4 is connected directly to the legs 46 and 47 and accumulates the operating time of the left rod packing 29. Timer T5 is also connected directly to the legs 46 and 47 and accumulates the operating time of the left piston rod 28.

'Timer T-6 is directly connected to the legs 46 and 47 and is used to accumulate the operating time of both left valves 36, valve seats 37 and right valves 41 and valve seats 42. In a normal preventative maintenance program, all valves and valve seats are changed out at one time.

The total operating time of the pump components in the right cylinder 24 is recorded on timers T-7 through T-11 (except the valves and valve seats as mentioned hereinbefore). Timer T-7 is connected directly to the legs 46 and 47 and accumulates the total operating time of the right liner 26. Timer T-8 has one lead connected to lower leg 46 and the other lead is connected through switch 54 to the upper leg 47. This timer is used to accumulate the operating time of the right piston No. 1. Timer T-9 is connected in the same manner as timer T-8 and is used to accumulate the operating time of the right piston No. 2. As in the case of the left hand cylinder liner, the right cylinder liner normally has a life span equal to twice the life of a piston so it is necessary to record the operating time of the first piston installed (No. 1) independently of the operating time of the second piston installed (No. 2). When a new liner is infold 34 and a right suction manifold 35. Left suction stalled both piston timers are set to zero, a new piston (No. l) is also installed and switch 54 set to connect timer T-8 to start recording the time of right piston No. 1. When a second right piston (No. 2) is installed in the right liner 26 the position of switch 54 is changed to connect timer T-9 to record the time on the second piston (N0. 2). Pilot lights P-3 and P4 indicate which of the timers T-8 or T-9, respectively, is connected to the circuit. Timer T-10 is connected directly to the legs 46 and 47 and accumulates the operating time of the right rod packing 32. Timer T-11 is also connected directly to the legs 46 and 47 and accumulates the operating time of the right piston rod 31. Timer T-12 is an extra timer that is connected directly to the legs 46 and 47. This timer can be used to replace any one of the timers in the circuit in case of failure. Also this extra timer can be used to record the operating time of some other component of the mud pump other than those enumerated hereinbefore.

The electrical time recording elements T-1 through T-12 are preferably of the 110 volt, 60 cycle AC synchronous motor driven rotating dial type elapsed time recorders. One commercially available timer that is very satisfactory is model 50-235022AAAA1 manufactured by General Electric Co., which records time in hours on rotating dials and has a zeroing knob for setting the dials to zero when a pump component is changed. However, other type electrical time recording elements can be used and the invention is not limited to a particular type time recorder element.

It is understood that the time recording device of the present invention may include only timers for a single cylinder mud pump, i.e. have only timers T-l through T-6 in a circuit. Thus the circuity between (and including) timers T-l and T-6 may be considered a module and may be repeated any number of times to provide separate modules for recording the operating time of components of any number of separate cylinders in one or more mud pumps.

The operation of the exemplary time recording device shown in the drawing will be explained with reference to the exemplary mud pump shown in the .drawing. Assume that the mud pump 20 is either new or has new cylinder liners, pistons, piston rods, rod packing, valves and valve seats. The pressure switch 50 is installed in the discharge line 45 (or in the air supply line leading to the air clutch as described hereinbefore) and connected to the timing device by wires 51 and 52. If the mud pump is powered by an electric motor the wires 51-52 can be connected to a conventional electrical switch which is actuated at the same time as the main switch to the electric motor. The plug 48 is plugged into a 110 volt outlet. The timer device can be powered by batteries if desired by use of suitable DC. voltage timer elements. Switch 49 is closed energizing upper and lower legs 47 and 46, respectively, and lighting pilot light P-S. Switches 53 and 54 are set to connect timers T-Z and T-8, respectively, into the circuit. All timers T-1 through T-12 are set to zero. When the mud pump is started switch 50 closes and actuates timers T-l, T-2, T-4 through T-8, and T40, T-11 and T-12. When the pump stops, switch 50 opens and the timers stop running. At the end of the normal life span (e.g. when 200 hours are recorded on timers T-4 and T-10), the left rod packing 29 and the right rod packing 32 is replaced with new packing and timers T-4 and T-10 are reset to zero. When, for example, 500 hours running time is recorded on timers T-Z, T-5, T-8 and T-11, the piston and piston rods are changed in the left cylinder 23 and the right cylinder 24. At this time the switches 53 and 54 are changed to connect timers T-3 and T-9 into the circuit. When timers T-1 and T-7 indicate a runnning time of say 800 hours, the left liner 25 and the right liner 26 are replaced and timers T-l and T-7 zeroed. At between about 1000-2000 hours the valves and valve seats are changed in both cylinders and timer T-6 is zeroed.

Most often the timing device will be installed on a mud pump which has been in operation for some time and the various replaceable components in the left and right cylinders all have different accumulated running times. In this case the total operating time of each separate component is determined from the log sheet that has been kept by the toolpushers on each shift. These total hours are then set on the hours dials of the individual timers which are designated as left liner etc. by a printing on the front face of the recording device. Then when each component in the left and right sides reaches its average life span the part is replaced and its particular timer is set to zero to automatically start recording the operating hours for the new component. When each component is changed, its life in hours can be entered on-a record sheet which can be used to record the life spans of all components and for calculating the cost of maintenance on the mud pump.

Thus it is seen that the time recording device of the present invention provides a means of automatically accurately recording the total operating times of various components in a mud pump. A successful preventative maintenance program can be carried out by changing the worn components of the pump after they have run for a normal life span and before they fail completely. The drilling rig operator no longer has to depend upon people to manually keep logs showing the operating times of the parts in the pump. No running logs of day to day operation are necessary when the time recording device of the present invention is utilized.

It is understood that the device of the present invention is subject to Wide modification without departing from the scope and spirit of this invention. Accordingly, the specific embodiments herein described and depicted are to be considered as merely illustrative and not as restricting the scope of the following claims.

What is claimed is:

1. A device for recording the total operating time of replaceable components in a reciprocating pump having at least one cylinder liner, piston, piston rod, rod packing, valve and valve seat comprising:

(a) electrical circuit means including a pair of electrical conductors;

(b) switch means in said circuit means adapted to continuously energize said circuit means when said machine is operating and open said circuit means when said machine is not operating;

(0) a first electrically operated time recording element directly connected to said circuit means;

(d) a second and a third electrically operated time recording element connected to one conductor of said circuit means; and

(e) switch means for connecting either said second or said third time recording element to the other conductor of said circuit means.

2. A device for recording the total operating time of replaceable components in a reciprocating pump having a pair of cylinder liners, a pair of pistons, a pair of piston rods, a pair of rod packings, and a plurality of valve and valve seats comprising:

(a) electrical circuit means including a pair of electrical conductors;

(b) a first switch in said circuit means adapted to continuously energize said circuit means when said machine is operating and open said circuit means when said machine is not operating;

(c) a pair of electrically operated time recording elements directly connected to said circuit means;

(d) a second pair and a third pair of electrically operated time recording elements connected to one conductor of said circuit means; and

(e) a pair of switch means for connecting one of said electrically operated time recording elements in each said second pair and said third pair to the other conductor of said circuit means.

3. A device for recording the total operating time of replaceable components in a reciprocating pump having at least one cylinder liner, piston, piston rod, rod packing, valve and valve seat comprising:

(a) electrical circuit means including a pair of electrical conductors;

(b) a first switch in said circuit means adapted to continuously energize said circuit means when said machine is operating and open said circuit means when said machine is not operating;

(c) a first group of electrically operated time recording elements directly connected to said circuit means;

((1) a second group of electrically operated time recording devices connected to one conductor of said circuit means; and

(e) a plurality of connecting means adapted to connect individual members of said second group of electrically operated time recording devices to the other conductor of said circuit means.

4. A device for indicating the total operating time of replaceable components in a reciprocating pump having a pair of cylinder liners, a pair of pistons, a pair of piston rods, a pair of rod packings, and a plurality of valve and valve seats comprising:

(a) a first pair of electrical time recording means for individually recording the total operating time of each component in a first set of components in said machine;

(b) circuit means directly connected to said first pair of electrical time recording means including a pair of electrical conductors;

(c) a switch in said circuit means, said switch being closed to continuously energize said circuit means when said machine is in operation and open when said machine is not operating;

(d) a second pair of electrical time recording means connected to one conductor of said circuit means;

(e) means to connect the other conductor of said circuit to one of said second pair of electrical time recording means to record the total operating time of one single component of said machine;

(f) means to disconnect the other conductor of said circuit from said one of said second pair of electrical time recording means and to connect the other of said second pair of electrical time recording means to the other conductor of said circuit to record the total operating time of the replacement component for said one single component;

(g) a third pair of electrical time recording means connected to one conductor of said circuit means;

(h) means to connect the other conductor of said circuit to one of said third pair of electrical time recording means to record the total operating time of another single component of said machine; and

(i) means to disconnect the other conductor of said circuit from said one of said third pair of electrical time recording means and to connect the other of said third pair of electrical time recording means to the other conductor of said circuit to record the total operating time of the replacement component for said another single component.

5. The device as defined in claim 4 wherein a fourth pair of electrical time recording means is connected to said circuit means for recording the operating time of each component in a second set of components in said machine.

6. A device for recording the operating time of replaceable components in a reciprocating pump having a cylinder liner, a piston, a piston rod, rod packing, valves and valve seats comprising:

(a) means to automatically accumulate and display the total operating time of said cylinder liner;

(b) means to automatically accumulate and display the total operating time of a first piston installed in said cylinder liner;

(c) means to automatically accumulate and display the total operating time of a second piston installed in said cylinder liner While preserving the display of the accumulated operating time of said first piston;

(d) means to automatically accumulate and display the total operating time of said piston rod;

(e) means to automatically accumulate and display the total operating time of said rod packing; and

(f) means to automatically accumulate and display the total operating time of said valves and valve seats.

7. A device for recording the operating time of replaceable components in twin cylinder reciprocating pump having a pair of cylinder liners, a pair of pistons, a pair of piston rods, a pair of rod packings, and a plurality of valves and valve seats comprising:

(a) independent means to automatically accumulate and display the total operating time of each one of said pair of cylinder liners;

(b) independent means to automatically accumulate and display the total operating time of each one of a first pair of pistons installed in said pair of cylinder liners;

(c) independent means to automatically accumulate and display the total operating time of each one of a second pair of pistons installed in said pair of cylinder liners while preserving the display of the accumulated operating time of each one of said first pair of pistons;

(d) independent means to automatically accumulate and display the total operating time of each one of said pair of piston rods;

(e) independent means to automatically accumulate and display the total operating time of each one of said pair of rod packings; and

(f) means to automatically accumulate and display the total operating time of said plurality of valves and valve seats.

References Cited UNITED STATES PATENTS 1,340,324 5/1920 Buck -58146 2,551,179 5/1951 Spencer 58145 2,679,038 5/1954 Cross et al. 58145 3,117,445 1/1964 Brown et al. 346-33 3,256,685 6/1966 Siewert 58-145 RICHARD B. WILKINSON, Primary Exqmi/ter. M, LORCH, Assistant Examiner, 

